We’ve all had those days when, even with the best of intentions, your workout gets sidetracked once you set foot in the gym. But with time at a premium, efficiency is a critical part of the fitness formula is you want to keep making progress.

“Almost everyone could benefit from getting a more effective workout in less time and reaching their goals sooner,” says Jennifer Beaton, VP and general manager at Western Athletic Clubs and a certified personal trainer at Bay Club San Francisco.

So take a look at these four common workout time wasters, and make a mental note to avoid them if you want to maximize your next trip to the gym:

1. Excessive rest. All those minutes spent sitting on the bench staring at your watch really add up. “If you can sit down and read the paper between sets, you are likely resting too long,” warns Beaton. To see better results with the very same moves, and to optimize your time, try super-setting exercises, such as push-ups and squats, to allow rest of a muscle group while you work another muscle group. Replacing station rest with active rest such as 30 seconds of high intensity cardio can also optimize calories burned and muscle recovery.

2. Steady-state cardio. In other words, those marathon (no pun intended) treadmill sessions. “We see many members who do the same 60 minutes of cardio at the same intensity every day for 15 years. These individuals no longer see improvements and often start to see declines in overall condition. They would benefit by mixing up their routine, adding intervals and high intensity work,” says Beaton.

3. Isolation exercises. “Life is full of dynamic movement, and therefore our workouts should simulate and enhance those efforts by using multi-joint, compound movements, such as squats, lunges and pull-ups as opposed to, for example, adductor/abductor machines or bicep curls. To get the most bang for your buck, focus on performing movements that recruit as many muscles as possible; those smaller secondary muscles will get plenty of work as they support the larger muscle groups during those movements,” Beaton adds.

4. Endless crunches. Likewise, if your goal is a great-looking midsection, ab-isolating exercises may miss the mark. “I often see people doing 15-20 minutes of crunches in hopes that it’ll deliver six-pack abs,” says Beaton. “Their time would be better spent on nutrition, a solid full-body strength routine, and a balanced cardiovascular program.”

How do you make the most of your time at the gym?